EFFECTS OF DELAYS AT DEPTH ON DIVER INSPIRED OXYGEN ...

Navy Experimental Diving Unit TA 02-02321 Duiifinch-Road .EDU TR- 4-13Panama City, FL 32407-7015 April 2004

EFFECTS OF DELAYS AT DEPTH ON DIVER INSPIREDOXYGEN PARTIAL PRESSURES IN SIMULATED LOCKOUTS

USING THE MK 25 MOD 2 UBA

rwII7v1Navy Experimental Diving Unit

20060210 065

Authors: V. L. Ruterbusch Distribution Statement A:M. J. Swiergosz Approved for public release;W. A. Gerth distribution is unlimited.

Navy Experimental Diving Unit TA 02-02321 BuilfiTIch Road 'FDU -r%- I %.Panama City, FL 32407-7015 April 2004

EFFECTS OF DELAYS AT DEPTH ON DIVER INSPIREDOXYGEN PARTIAL PRESSURES IN SIMULATED LOCKOUTS

USING THE MK 25 MOD 2 UBA

rwtn I

Navy Experimental Diving Unit

Authors: V. L. Ruterbusch Distribution Statement A:M. J. Swiergosz Approved for public release;W. A. Gerth distribution is unlimited.

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11. TITLE (Include Security Classification)(U) EFFECTS OF DELAYS AT DEPTH ON DIVER-INSPIRED OXYGEN PARTIAL PRESSURES IN SIMULATED LOCKOUTS USING THE MK 25 MOD

2 UBA

12. PERSONAL AUTHOR (S)V. L. Ruterbusch, M. J. Swiergosz, and W. A. Gerth

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19. ABSTRACT (Continue on reverse if necessary and identify by block number)Divers using the MK 25 provided data on partial pressures of oxygen (PO2) during deep lockout simulations at 60 feet of seawater (fsw), simulations in which delays of 1,10, and 30 min at depth were manipulated before ascent to 15 fsw. Divers assumed a vertical orientation and maintained a restful state in euthermic water conditionsthroughout the procedure. Eighty-one of 88 dives were completed without violating P0 2 safety criteria. Two dives in the one-minute delay condition (n = 25) and threedives in the 10 min delay condition (n = 35) resulted in low P0 2 (:90.16 atmospheres absolute [ATA]), and two dives in the 30 min delay condition (n = 28) resulted in high

P0 2 (->1.70 ATA for more than 10 min). Binary confidence limits for violating P0 2 safety criteria were between 0.003 and 0.320.

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.. CONT NTS b

Page No.

DD Form 1473 ........................................................................................... iContents .............................................................................................. ii

Introduction .......................................................................................... 1Methods ................................................................................................. 1

General .............................................................................................. 1Experimental Design and Analysis ..................................................... 1Equipment and Instrumentation .................................................... 2Data Reduction and Analysis ......................................................... 2OSF Diving Procedures ................................................................. 3

Results ................................................................................................. 5Data Sum m ary ............................................................................... 5P0 2 Outcomes ...................................... 7

Discussion ........................................................................................... 8Conclusions and Recom mendations ...................................................... 11References .......................................................................................... 12

Appendix A: Depth and P0 2 x Tim e Profiles ..................................... A-1Appendix B: Dive and P0 2 Sum m ary Data ....................................... B-1

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INTRODUCTION

The Advanced SEAL Delivery System (ASDS) is a small, dry submarine capable ofsupporting a wide range of operational scenarios and depths. It allows U.S. NavySEALS to leave the host sub and approach targets in an environment that preservesphysical readiness. To reduce the likelihood of detecting the ASDS from the surface,U.S. Navy SEALS may have to perform lockout (LO) operations using the MK 25 MOD2 (MK 25) Underwater Breathing Apparatus (UBA) at depths greater than 20 feet ofseawater (fsw). Pursuant to previous testing by Navy Experimental Diving Unit (NEDU)in which it was shown that MK 25 LO procedures could be undertaken from a depth of50 fsw,3 the Commodore of Naval Special Warfare Croup THREE(NAVSPECWARGRP3) requested development of MK 25 LO procedures from a depthof 60 fsw. 1'2 Such procedures were designed and tested in NEDU's Ocean SimulationFacility (OSF) to characterize the risks incurred during representative scenarios.

Central nervous system (CNS) oxygen toxicity and hypoxia are the major risksassociated with use of the MK 25 UBA in deep LO operations, and only one excursionto any depth greater than 20 fsw is permitted in a 4-hour dive using the MK 25. Diverinspired oxygen partial pressure was monitored throughout the course of each test as afactor governing these risks, and to determine whether the procedures cause divers toexceed 02 exposure limits. Tested procedures also incorporated preascent delays of 1,10, or 30 minutes, because U.S. Navy SEALS and support divers indicated thatoperators locking out from the ASDS may have to delay their ascent to "normal" transitdepth of 15 to 20 fsw for as long as 30 minutes.

METHODS

EXPERIMENTAL DESIGN AND ANALYSIS

U.S. Navy and Marine Corps divers experienced in MK 25 operations and trained toconduct free ascents participated in the trials. All divers received additional training inthe NEDU test pool to become familiar with the "de-purge" procedure before proceedingto the OSF trials.

The OSF wetpot was configured to support eight divers in euthermic water (75-85 OF).Testing was conducted over a 3 day period from 26 to 28 October 2003. A faulty 02 fuel

cell discovered on the first dive reduced the number of divers to seven per set for theduration of the study. During each evolution, the complex was pressed on air to 57 fsw(60 fsw with a three-fsw offset). Divers then completed a 1, 10, or 30-minute delay at 60fsw before ascent.

Oxygen partial pressures were recorded throughout all dives. Safety parameters wereselected to prevent hypoxia and CNS 02 toxicity and to avoid exceeding operationalexcursion limits. Procedures were considered "safe" if inspired oxygen levels from theMK 25 did not fall below 0.16 atmospheres absolute (ATA), increase above 1.7 ATA for10 minutes, or exceed 2.4 ATA at any time. A dive was aborted if any of these criteriawas violated.

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EQUiPMLENT AND iNSTRUMENTATiON

Each MK 25 was instrumented with a Teledyne R-1ODS 02 fuel cell positioned in a gassample block at the base of the inhalation hose. Linear operational calibration of R-1ODS fuel cells was obtained from measured voltage outputs flushed at sea level withair (P0 2 = 0.21 atmospheres [ATM]) and 100% 02 (P0 2 = 1.00 ATM) each day beforediving. Data from each diver's 02 cell was transmitted to the medical deck in real timeand recorded as P0 2 in atmospheres by converting outputs of measured fuel cellvoltage. Fuel cell data was logged at two-second intervals with a National InstrumentsLabVIEW (Austin, TX) data acquisition system.

The OSF was equipped with a two-tiered diver platform. The upper level, or highstand,was set at a level approximately three feet below the OSF waterline. Thus, the diver'storso and MK 25 were both above the waterline while he was standing on the highstand.The lower level was approximately six feet below the highstand. Both levels couldcomfortably accommodate eight divers.

Depth was recorded with a Druck 0-50 psi pressure gauge, and water temperature was

obtained with a YSI Incorporated (Yellow Springs, OH) 700 series thermistor.

DATA REDUCTION AND ANALYSIS

Each diver's inspired P0 2 was monitored with a Teledyne R-1 ODS 02 fuel cellpositioned in a gas sample block at the base of the inhalation hose on each MK 25.Voltage output from each fuel cell was passed by umbilical to a real-time dataacquisition system on the OSF Medical Deck, where it was converted to P0 2 inatmospheres and recorded for the diver at midchest depth.

MK 25 P0 2 values remained below 1.0 ATA, hence within the linear calibration range ofthe R-1 ODS fuel cells, nearly all the time. Consequently, recorded P0 2 values did notrequire correction for nonlinearities in fuel cell output versus P0 2 that occur at higherP0 2

5 . Most of the P0 2 values that exceeded 1.0 ATA resulted from an 02 fuel cell"voltage spike" following a MK 25 02 add-valve actuation. Recorded dive profiles wereanalyzed with software modified from that developed in earlier work.6 Recorded P0 2values were smoothed with a 25-point moving quadratic convolute. Smoothed diveprofiles are given in Appendix A. Summary information about each profile was compiledfrom these smoothed profiles and is presented in Appendix B.

The summary information for each profile was compiled with respect to depth-relateddive events; Leave Surface (LS), Reach Bottom (RS), Leave Bottom (LB), and ReachFirst Stop (FS). The times at which each of these events occurred in a profile; TLS,TRS, TLB, and TFS, respectively; were determined from recorded depths smoothedwith an 11-point moving quadratic convolute. TLS was determined as the time when thesmoothed depth first exceeded the mean smoothed depth of the first 30 seconds of therecorded profile plus one fsw, and thereafter failed to fall shallower than five fsw. TRBwas determined as the time after TLS when the smoothed depth during the ensuing 20-second period (a 10-record interval) first changed by 0.1 fsw/min or less. The average

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descent rate in the dive was then calculated from raw depth data during only thosesections in the TLS-->TRB interval in which the local moving average depth changeexceeded 3 fsw/min. TLB was determined as the time after TRB when the meansmoothed depth during the next 30 seconds (a 15-record interval) was at least one fswless than the prevailing smoothed depth. Finally, TFS was determined as the time afterTLB when the mean smoothed depth during the next 30 seconds first changed by 0.1fsw or less.

Summary information for each profile includes the P0 2 minimum and maximum reachedduring each of three periods in the profile: (1) "RB thru Procedure," defined the periodbetween TRB and when the diver started breathing on the MK 25, (2) "PreascentDelay," defined as the period between when the diver started breathing on the MK 25and TLB, and (3) "Ascent," defined as the period between TLB and TFS. These threeperiods in a typical dive are illustrated in Figure 1. Time-weighted average P0 2 duringthe first two of these periods is also included.

80 i8 RB through Procedure

60• L•-. Preascent DelaySso

60--

40

-" . ". - Ascent

O 20

0~ ~ ~ 11

283

8 13 18 23 28 33TLS TLB

TRB TFS

Time (min)

Figure 1. Typical depth versus time profile illustrating the three periods for which P0 2summary information was compiled.

OSF DIVING PROCEDURE

Divers set up the MK 25 according to standard operating procedures, but did not

perform an 02 purge.

Connections for dive instrumentation were completed in the OSF trunk. The diversentered the wetpot and moved to their positions facing each other in buddy pairs on thehighstand, where they remained standing with heads and entire torsos, including UBAs,out of the water to simulate LO positions in the ASDS. To allow their MK 25s to equalizeduring the ensuing compression, the divers placed their mouthpiece barrel valves in

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dive position and executed the following de-purge procedure with their 02 cylindervalves closed:

(a) Deplete MK 25 breathing bag volume by inhaling through mouth from the UBA T-bit and exhaling into the surrounding atmosphere through nose, repeating untilbag is empty;

(b) Add air to the MK 25 bag by inhaling chamber air through the nose and exhalinginto MK 25 via the T-bit, repeating until bag is at a comfortable breathing volume.

(c) Repeat steps (a) and (b) four times;

(d) Medical Deck personnel check UBA P0 2. Proceed with chamber press to LOdepth if UBA P0 2 between 0.16 ATA and 0.22 ATA, as registered via the R10-DS 02 fuel cell. If UBA P0 2 exceeds 0.22 ATA, repeat steps (a), (b) and (d).

Upon reaching 57 fsw, as indicated on the Charlie Manual Operation Panel (MOP)digigauge, divers executed instructions transmitted from the Medical Deck via the trunktender on how to prep their rigs before submerging three feet below the water's surface.To try to rectify procedural deficiencies that arose as the study continued, investigatorsmodified these instructions twice during the protocol.

Subjects on dives 1-58 received the original instructions: "At the end of a normalinhalation, go on your rig, exhale one tidal volume breath of chamber air into your MK25, open your 02 bottle (all the way open and back one-quarter turn), immediatelysubmerge your head, and move from the highstand to the middle platform in the OSF."

The low P0 2 safety criterion (P0 2 < 0.16 ATA) was violated during the delay at depth infour dives performed with this procedure, a result raising the suspicion that chamber airwas being pressed back into the breathing bags during compression, was increasingbag volume, and was delaying subsequent actuation of the 02 add-valve. This train ofevents would have increased the likelihood of hypoxia before ascent.

Accordingly, subjects in dives 59-77 performed a modified procedure intended todecrease their MK 25 breathing bag volumes before they submerged. They received thefollowing pre-submergence instruction: "Completely empty your breathing bag, inhalingthrough your mouth and exhaling through your nose. When the bag is flat, take onenormal inspiration through your nose and exhale it into the rig; open your 02 cylindervalve, immediately submerge your head, and move from the highstand to the middleplatform in the OSF."

Despite this procedural modification, an additional hypoxic event occurred. To increasethe initial UBA P0 2 in dives 78-92, therefore, it was decided to add a one-secondmanual 02 addition to the procedure before divers submerged. Divers were thus giventhe following presubmergence instruction: "Completely empty your breathing bag,inhaling through your mouth and exhaling through your nose. When the bag is flat, takeone normal inspiration through your nose and exhale it into the rig, open your 02cylinder valve, perform a one-second manual 02 addition, and immediately submergeyour head and move from the highstand to the middle platform in the OSF."

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in aii cases, the uSF was decompressed to 15 fsw at a rate of 30-6U fUMtr in afL1r thescheduled delay at depth was completed. Divers breathed in an open-circuit mannerduring ascent by making short inhalations from the MK 25 followed by slow, prolongedexhalations through the nose. Divers were instructed to avoid exhaling into the MK 25. Ifthey found that this breathing pattern was insufficient to prevent overinflation of the UBA("chipmunk cheeks"), they were advised to allow some air to "burp past" their T-bitmouthpieces. The Dive Watch Supervisor reported depths every 10 fsw on ascent to 15fsw so that divers could anticipate the amount of exhaled air volume required to ascendsafely.

After reaching 15 fsw, divers executed a two-empty/fill underwater UBA purgeprocedure. Each diver first completely emptied his breathing bag by inhaling from hisUBA and exhaling through his nose, and then completely filled his bag with oxygen byactivating his 02 add valve for 6 seconds or until he sensed his bag pressing on hischest. This sequence was then repeated, ending with a UBA bag volume comfortablefor swimming. The OSF remained at 15 fsw for 10 minutes before traveling to thesurface at a rate of 30 ft/min. On the surface, divers stopped breathing from their rigs,secured their mouthpieces in "surface mode," and closed their oxygen bottle cylindervalves. Divers then exited the OSF in the reverse order of their entry.

Divers that developed problems at any time during the evolution were instructed to takethe appropriate action (e.g., to manually add 02 to their rigs if UBA P0 2 fell below 0.16ATA), move to the highstand, go off their rigs, and breathe chamber air for theremainder of the dive.

Post-dive debriefs were conducted after each dive to solicit diver feedback and confirmthat the procedures had been performed as intended. All deviations from the intendedLO procedure were noted in the investigator's log.

RESULTS

DATA SUMMARY

Of 92 dives undertaken, one was aborted because of 02 fuel cell malfunction, andanother was aborted because of water in the rig. Two additional dives were abortedwhen the divers failed to open their 02 cylinder valves as they had been instructed. Theremaining 88 dives, completed by 37 different divers, provided data suitable foranalysis. Eighty-one dives (81/88) were successfully completed without violating P0 2safety criteria. One example of such a dive is presented in Figure 2. Seven dives (7/88)resulted in violations of P0 2 safety criteria and were aborted. Examples of such divesare given in Figures 3 and 4. Complete depth and inspired P0 2 profiles for all 88 divesare illustrated in Appendix A, and summary P0 2 data are tabulated in Appendix B.

5

80 -- Pressure 2.0P02

~60- 1.5

40 1.00

020 0.5

0 '- 0.0

0 10 20 30 40 50 60

Time (min)

Figure 2. A depth and P0 2 versus time profile for a dive completed without violatingP0 2 safety criteria. Dashed lines indicate minimum (0.16 ATM) and maximum (1.7 ATM)P0 2 markers (Appendix A: Dive 1).

80 -i-Pressure 2.0MK 25 P02

j60 - - CHAMBER AIR 3 1.5~

40 1.0

0 20 - 0.5

0 - -1 ] 0.0

0 10 20 30 40 50 60

Time (min)

Figure 3. A depth and P0 2 versus time profile for a dive in which the low P0 2 safetycriterion was violated during ascent. Dashed lines indicate minimum (0.16 ATM) andmaximum (1.7 ATM) P0 2 markers. The diver started breathing chamber air atapproximately 18 minutes (Appendix A: Dive 7).

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". . Pressure 2.0

P02

60 CABE-R-. .I1.-

S40-- 1.0•. MK 25 C14

CL

S20 0.5

0-- . 0.00 10 20 30 40 50 60

Time (min)

Figure 4. A depth and P0 2 versus time profile for a dive in which the high P0 2 safetycriterion (P02 > 1.7 ATM for longer than 10 minutes) was violated in the preascent delayperiod. Dashed lines indicate minimum (0.16 ATM) and maximum (1.7 ATM) P0 2markers. The diver started breathing chamber air at 37 minutes (Appendix A: Dive 84).

P0 2 OUTCOMES

Incidents of observed P0 2 outcomes under each delay condition are given in Table 1.No dives resulted in P0 2 >- 2.4 ATA. Five dives resulted in P0 2•_ 0.16 ATA, and twodives resulted in P0 2 -> 1.7 ATA for 10 minutes. Violations of P0 2 safety criteria (n = 2)in the one-minute delay condition occurred during ascent to 15 fsw. Violations of P0 2

safety criteria occurred during 10-minute (n = 3) and 30-minute (n = 2) delays at depth.Air leaked from the mask and violated P0 2 safety criteria (n = 2) during the 30-minutedelay. Symptoms associated with these violations occurred only once (Dive 49), in adiver pulled for P0 2•< 0.16 ATA during the 10-minute delay. However, he reported thesymptoms, which he described as "warm and tingly" lips and legs, only during thepostdive interview, when he also noted that all symptoms completely resolved withinseconds after he began breathing chamber air.

Table 1.Frequency of P0 2 Outcomes*

Delay at Depth (min) Acceptable P0 2 P0 2•< 0.16 P0 2Ž- 1.71 23 2 0

10 32 3 030 26 0 2

*The first four dives with P0 2 < 0.16 occurred under the original procedure, in which the UBA was emptied only before descent.One incident of low P0 2 occurred after the procedural modification that included a second UBA emptying at depth (during a 10-minute delay). Both dives with P0 2 >- 1.7 occurred under the final procedure tested, that which included a manual 02 addition afterthe second UBA emptying at depth (see p. 4 for details).

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Table 2 lists the binary confidence limits for observed incidents of P0 2 safety criteriaviolations at each delay.

Table 2.Binary Confidence Limits for the probability of Violating P0 2 Criteria*

Delay at Depth (min) Confidence Limits (99%1 0.004 - 0.320

10 0.009 - 0.27930 0.003 - 0.290

*P02! 0.16 ATA or P0 2 _> 1.7 ATA for 10 min.

DISCUSSION

The ASDS is a small, dry submarine capable of supporting a wide range of operationalscenarios and depths. It allows Navy SEALS to leave the host submarine and approachtargets in an environment that reduces the impact of environmental stressors onphysical readiness. Since the ASDS is larger than the current delivery vehicle, it may bedesirable to perform LO operations at depths greater than 20 fsw to avoid detectionfrom the surface.

Original ASDS LO plans involved using an air hookah system that would allow SEALSto lock out from a minimum depth of 60 fsw. This system included an ascent line up to atransit depth of 15 to 20 fsw, where divers could shift from air to the MK 25 UBA. Forseveral engineering reasons, the hookah system did not become available, and noplans for installing it exist. Therefore, this research simulated procedures for LO with theMK 25.

The problem with using the MK 25 during a LO procedure at 60 fsw is the possibility ofencountering unacceptably low or high diver-inspired P0 2 . Markers of hypoxia andhyperoxia were selected as safety parameters for our simulated LO procedures. Onediver reported symptoms associated with P0 2 -< 0.16, a report suggesting that the lowP0 2 safety criterion was not excessively conservative. High P0 2 safety criteria wererelated to losing an operational excursion or provoking CNS 02 toxicity. Symptomsassociated with CNS 02 toxicity were not reported in the two incidents of high P0 2 thatoccurred in the present dives.

Lockout procedures tested in this study were designed to trap nitrogen (N2) in the MK25 closed-circuit breathing loop in order to dive the UBA as a de facto nitrox rig atdepth. This design intent was accomplished by having divers employ the de-purgeprocedure (p. 4) on air in the simulated ASDS moon pool before exiting the ASDS at LOdepth. After this procedure at 60 fsw, the P0 2 in the MK 25 and in the diver's lungs isapproximately 0.59 ATA, a level that poses no risk of hypoxia or CNS 02 toxicity.However, the MK 25 02 add-valve does not actuate until the breathing bag decreases toa threshold minimum volume. A sufficiently large initial MK 25 volume of air may

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consequently support diver respiration for several minutes before the breathing bagvolume decreases to the point where the 02 add-valve actuates. Under such conditions,inspired P0 2 will continue to fall. The diver may either become seriously hypoxemic atdepth or during subsequent ascent, when further pressure-driven P0 2 decreases occur.For example, if a diver leaves 60 fsw with a P0 2 less than 0.40 ATA and his 02 add-valve has not actuated, he may become hypoxic before he reaches transit depth (15 to20 fsw). All of the P0 2 safety violations (n=2) after one-minute delay at depth werehypoxic events during ascent in accord with this scenario. If a diver's delay time is lessthan 10 minutes, he should therefore be instructed to perform a two-second manual 02addition before ascent, to avoid hypoxia as his P0 2 decreases during that ascent.

If the breathing bag is not overinflated at the start of the LO procedure, the 02 add-valve

will actuate, add oxygen as it is consumed, and increase the UBA P0 2 . As long as the

initial N2 content is retained in the closed loop, P0 2 will approach a steady state, whereit will be maintained indefinitely. However, any lost N2 will be replaced by 02, causingUBA P0 2 to increase to potentially unacceptable levels depending on depth. Two suchcases occurred during the longest delay time tested (30 min), with inspired P0 2increasing to values greater than 1.7 ATA for more than 10 min. These exposures hadP0 2 values in excess of that incurred by breathing 100% 02 at 20 fsw, and becausethese P0 2 values persisted for more than 10 minutes, the exposures exceeded thethreshold to be counted as an excursion in MK 25 diving. Operational occurrence ofsuch an exposure would consequently force the LO to be logged as the only 02excursion allowed under current 02 exposure limits in the U.S. Navy Diving Manual.8

Such use of the only allowed excursion during LO must be avoided, because divers willalso need to lock in to the ASDS at the end of the mission. This lock-in (LI) willpresumably occur at a depth greater than 20 fsw, and consequently require its ownexcursion. Interviewed operators indicated that such an LI might also have a delay aslong as 30 minutes. To address this possibility, future testing should include the 60 fswLO, a mission swim with one excursion, a return swim, and a 30-minute delay before LI.

Although we observed seven P0 2 safety criteria violations in 88 LO procedures, thesafety of using the MK 25 in operational LO procedures at depth remains uncertain.While immersed in euthermic water, our test subjects wore shorts and t-shirts and werecompletely at rest. They were therefore breathing the MK 25 in a slow, shallow fashionwith presumably very little consumed 02. Operational conditions (i.e., cold water andexercise) should induce greater 02 consumption, trigger earlier and more reliable 02add-valve actuation, and reduce the likelihood of low P0 2 events. Similarly, divers in thepresent tests remained in an upright (vertical) position. Postdive interviews suggestedthat having divers in a horizontal swim position might reduce their work of breathing andair leakage, and thereby foster their retention of residual N2 in the UBA and mitigate thelikelihood of unacceptably high P0 2 events. In any case, one essential observation isclear: adherence to procedure is critical to overall success. A dive supervisor in theASDS moon pool will almost certainly be required to ensure that divers comply with allaspects of the procedure. Such function would be facilitated by use of a pre-dive check-off sheet, and include performance of a hands-on check on each diver to ensurebreathing bags are not over-inflated, 02 cylinders are open, etc.

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Additional considerations for future testing should include operational watertemperatures and having divers perform fight exercise in a prone, horizorital (sw•i)position at depth on cycle ergometers.

CONCLUSIONS AND RECOMMENDATIONS

"* Seven incidents of unacceptably low or high inspired P0 2 occurred during 88 LOprocedures at 60 fsw.

"* Unacceptably low or high P0 2 might be mitigated by light exercise, operationalwater temperatures (cold), procedural modifications, and training - all of whichrequire further testing.

"* Open water LO procedures using the MK 25 at 60 fsw are not recommended atthis time.

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REFERENCES

1. NSWG3 E-mail Itr 3963 Ser NSWG3 Commodore of 19 May 03.

2. NSWG3 E-mail Itr 3963 Ser NSWG3 N312A of 10 Jul 03.

3. G. S. Conley, ASDS MK 25 MOD 2 Lockout/Lock-in Procedures, NEDU TL02-01,Navy Experimental Diving Unit, Jun 2002.

4. U.S. Naval Sea Systems Command, Task Assignment 02-02: Evaluation of UBASuitable for the Advanced Seal Delivery System (ASDS), 04 Jan 2002.

5. W. A. Gerth, K. A. Gault, and S. J. Stanek, Empirical Evaluation of the MK 16 MOD

1 UBA Breathe-Down Procedure, NEDU TR 03-14, Navy Experimental Diving Unit,July 2003.

6. W. A. Gerth and T. M. Johnson, Development and Validation of 1.3 ATA P0 2-in-HeDecompression Tables for the MK 16 MOD I UBA, NEDU TR 02-10, NavyExperimental Diving Unit, August 2002.

7. F. K. Butler and E. D. Thalmann, Purging Procedures for the Draeger LAR VUnderwater Breathing Apparatus, NEDU TR 05-84, Navy Experimental Diving Unit,March 1984.

8. Commander, Naval Sea Systems Command, U.S. Navy Diving Manual, Revision 4,Publication SS-521-AG-PRO-010 (Arlington, VA: NAVSEA, 1999).

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APPENDIX A: Depth and P0 2 vs. Time

80 -Pressure 2.0P02

j60- 1.5 '

40 1.0

00O20 -- 0.5

0 0.00 10 20 30 40 50 60

Time (min)

Dive 1. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

802.8--Pressure 2.0

P02

60 1.5

40 1.0 *0~0.

a 20-- 0.5

o0 ... 0.00 10 20 30 40 50 60

Time (min)

Dive 2. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Diver pulled; P0 2 < PO2min during ascent.

A-1

inPressure .2.0

P02

6060 1.5

40-4 1.00. 0

20- 0.5

0F 0.00 10 20 30 40 50 60

Time (min)

Dive 3. Dashed lines indicate PO 2min (0.16 ATM) and PO2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

802 ,80-Pressure 2.0

P02

40_6 1.0

1 N0L

20 - -- 0.5

0 1 1,0.00 10 20 30 40 50 60

Time (min)

Dive 4. Dashed lines indicate PO2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Dive aborted before leaving surface due to H20 in the rig.

A-2

0 .Pressure 2.0P02

S60 1.5

40 40 1.0 N0. 0

13 20 0.5

0 .0.00 .10 20 30 40 50 60

Time (min)


80-8--Pressure 2.0

P02

60-1.

-40 1.0

20 0.5

02 40 0. 0

0 10 20 30 40 50 60

Time (min)

Dive 6. Dashed lines indicate PO 2min (0.16 ATM) and PO2max (1.17 ATM)markers. Aborted before leaving surface due to defective 02 fuel cell. Diverposition lost for remainder of study (maximum number of divers in the OSFreduced from 8 to 7.)

A-3

iu -Pressure 2.0

P02

60 ~1.5

4040 1.0 %w

20 0.5

0I 0.0

0 10 20 30 40 50 60

Time (min)

Dive 7. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Diver pulled; P0 2 < P02min during ascent.

80Pressure 2.0P02

60 1.5

4040 1.0

0LS20 0.5

0 - - 0.0

0 10 20 30 40 50 60

Time (min)

Dive 8. Dashed lines indicate PO2min (0.16 ATM) and P0 2ma, (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-4

-Pressure 2.0P02

60 1.5

40 - 1.0404

C0

20- 0.5

0 , 1 10.00 10 20 30 40 50 60

Time (min)

Dive 9. Dashed lines indicate PO2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Unexplained increased noise in signal. Dive completed without violatingP0 2 safety criteria.

802.80n Pressure 2.0

P02

S60 1.5

40 1.0

S20 0.5

0 I I I 0.0

0 10 20 30 40 50 60

Time (min)

Dive 10. Dashed lines indicate PO2min (0.16 ATM) and PO2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-5

0 -Pressure 2.0P02

"6060 1.5

:40-- 1.00

020 0.5

0* 0.0

0 10 20 30 40 50 60

Time (min)

Dive 11. Dashed lines indicate PO2mrin (0.16 ATM) and PO2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure 2.0P02

60 1.5tE.~40- ~1.0CL 0020 0.

0 T - 0.00 10 20 30 40 50 60

Time (min)


A-6

du Pressure 2.0P02

S60 1.5

400

20 0.5

0~ 0.00 10 20 30 40 50 60

Time (min)


80Pressure 2.0P02

S60 1.5

40 1.0

0 20- 0.5

0 I 0.0

0 10 20 30 40 50 60

Time (min)

Dive 14. Dashed lines indicate PO2 min (0.16 ATM) and PO2 max (1.17 ATM)markers. Dive aborted due to P0 2 -< PO2min. 02 bottle was closed, therefore datawas not included during analyses.

A-7

.80 .Pressure - 2.0P02

60 1.5

:40- 1.0

20- 0.5o

0 I I i 0.00 10 20 30 40 50 60

Time (min)

Dive 15. Dashed lines indicate PO2min (0.16 ATM) and PO2max (1.17 ATM)markers. Unexplained increased noise in signal. Dive completed without violatingP0 2' safety criteria.

80 Pressure 2.0

P02

6060 1.5

:40- 1.0

D20 0.5

0 i i i 0.00 10 20 30 40 50 60

Time (min)Dive 16. Dashed lines indicate PO 2min (0.16 ATM) and PO2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-8

OU Pressure 2.0P02

620 1.5

4 02- -ELll I .40 - I.

20-- -.

0 10 20 30 40 50 60

Time (min)


80Pressure 2.0

P02

60 1.5

40- 1.0

S20- 0.5

0 I0.0

0 10 20 30 40 50 60

Time (min)

Dive 18. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Dive aborted due to P0 2 -< PO2min. 02 bottle was closed; not included indata analyses.

A-9

Pressure 2.0P02

60 1.5

:402 _.

20- . 0.5

0 ! i i i - 0.00 10 20 30 40 50 60

Time (min)

Dive 19. Dashed lines indicate PO2rnin (0.16 ATM) and PO2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure 1 2.0P02

-60 15i-

S40 1.00. 604) CO20 0.5

0* I i i 0.0

0 10 20 30 40 50 60

Time (min)


A-10

U i- Pressure 2.0P02

60 1.5

4 0 -- 1 .0400

20 0.5

0 _L1 I - 0.0

0 10 20 30 40 50 60

Time (min)


80Pressure 2.0P02

60-- 1.5

4040 1.0

S20- 0.5

0 I40.00 10 20 30 40 50 60

Time (min)


A-11

80n Pressure 2.0P02

640 1.0

20

20-' 0.5

A-10.00 10 20 30 40 50 60

Time (min)Dive 23. Dashed lines indicate PO2min (0.16 ATM) and PO2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure 2.0P02

601.5

40 1.00.o00

13 20 0.5 CL

0 40 100.00 10 20 30 40 50 60

Time (min)


A-12

80- Pressure 2.0SP02

60-- 1.5

4040 1.0

S20-- 0.5

0 0.00 10 20 30 40 50 60

Time (min)


80 -Pressure 2.0P02

60 1.5

40 1.0

020 - 0.5 C

01 0.0

0 10 20 30 40 50 60

Time (min)

Dive 26. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. P0 2 < PO2min at 02 valve actuation. Dive completed without violatingP0 2 safety criteria.

A-13

80 Pressure 2.0P02

60 1.5

40 1.0

00O20 -- 0.5

0% 0.00 10 20 30 40 50 60

Time (min)

Dive 27. Dashed lines indicate PO2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80 - Pressure 2.0P02

60-1.

40 - 1.0

00020 - 0.5

0 1 1 0.00 10 20 30 40 50 60

Time (min)


A-14

802 .80n Pressure 2.0

P02

60 1.5

40 1.0o0. ~

20 -I 0.5

0 0.00 10 20 30 40 50 60

Time (min)

Dive 29. Dashed lines indicate PO 2min (0.16 ATM) and PO2 max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure 2.0P02

60- 1.5

., 40I 1.0

20 0.5

0 I I0.0

0 10 20 30 40 50 60

Time (min)

Dive 30. Dashed lines indicate PO2 min (0.16 ATM) and PO2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-15

80Pressure 2.0P02

60 1.5

40 1.0

20 0.5

0 J i i I 0.00 10 20 30 40 50 60

Time (min)

Dive 31. Dashed lines indicate PO2min (0.16 ATM) and PO 2max (1.17 ATM)markers. P0 2 < PO2min at 02 valve actuation. Dive completed without violatingP0 2 safety criteria.

80 Pressure 2.0P02

60,.40 • 1.5

:40-

a- 0~O20 10.5

0 I 0.0

0 10 20 30 40 50 60


A-16

Pressure , 2.0P02

60 1.S40 1.0

20 0.5

0 -0.00 10 20 30 40 50 60

Time (min)


80Pressure 2.0P02 T

60 !1.5

400aC,

020 0.5

0 4 {0.00 10 20 30 40 50 60

Time (min)


A-17

u-Pressure + 2.0P02

,60 1.5

40 1.0

20 0 .5

0' 0.00 10 20 30 40 50 60

Time (min)


80Pressure + 2.0P02

60- -'1.5

a40- 1.0 M

D20 0.5

0 I I ; 0.0

0 10 20 30 40 50 60

Time (min)


A-18

80Pressure 2.0

P02

601.

40 1.0

2020 0.5

0 , I I 10.00 10 20 30 40 50 60

Time (min)


80Pressure 2.0P02

60 o1.5 S• E40-- 1.0

00I 20 - 0.5

0 , I 0.0

0 10 20 30 40 50 60

Time (min)

Dive 38. Dashed lines indicate PO 2 min (0.16 ATM) and PO2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-19

80 Pressure 2.0P02

640 1.5

40 S

20 0.5

0 L'- 0.0

0 10 20 30 40 50 60

Time (min)


80Pressure 2.0

P02

60 ~1.5

40 1.0 04

4) CS20 -0.5

0* I0.0

0 10 20 30 40 50 60

Time (min)


A-20

80Pressure 2.0P02

60- 1.5

:40 1.0

20- 0.5

0- -- 40.00 10 20 30 40 50 60

Time (min)

Dive 41. Dashed lines indicate PO 2 min (0.16 ATM) and PO2 max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure 2.0P02

60- -1.5

40 1.0

S20-- -- 0.5

0 - I 0.0

0 10 20 30 40 50 60

Time (min)


A-21

80 "-Pressure 2.0P02

60 -1.5

:40240-- 1.0

0.5

20- 0.5IiT

0 i 0.00 10 20 30 40 50 60

Time (min)

Dive 43. Dashed lines indicate PO 2 min (0.16 ATM) and PO 2max (1.17 ATM)markers. P0 2 < PO2min at 02 valve actuation. Dive completed without violatingP0 2 safety criteria.

80 Pressure 2.0P02

60 1.5

40 1.0

0LO20 -,0.5

0 • 1 100.0

0 10 20 30 40 50 60

Time (min)


A-22

Ou -Pressure 2.0

P02

S260 1.5

40, 1.0

S20-. -0.50

0 0-.00 10 20 30 40 50 60

Time (min)

Dive 45. Dashed lines indicate PO2 min (0.16 ATM) and PO 2max (1.17 ATM)markers. Diver pulled; P0 2 < PO2min before ascent.

80 Pressure 2.0P02

"60 - 1.5

40 1.0

20- 0.5

0 1 _0.0

0 10 20 30 40 50 60

Time (min)


A-23

80 Pressure 2.0P02

60'

S20 - 0.50.5

00

0 10 20 30 40 50 60

Time (min)Dive 47. Dashed lines indicate PO 2min (0.16 ATM) and PO2max (1.17 ATM)markers. P0 2 < PO2min at 02 valve actuations. Dive completed without violatingP0 2 safety criteria.

80Pressure i 2.0P02

60 !1.5

40 1.0

0~020 ,, 0.5

0 0.0

0 10 20 30 40 50 60

Time (min)

Dive 48. Dashed lines indicate PO 2min (0.16 ATM) and PO2m.x (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-24

802.80- Pressure 12.0

P02

60 1.5E

.~401.

0. 0

20 0.5

0 0.0

0 10 20 30 40 50 60

Time (min)Dive 49. Dashed lines indicate PO2min (0.16 ATM) and PO2max (1.17 ATM)markers. Diver pulled; P0 2 < PO2min before ascent.

80 Pressure 2.0P02

-~60- -'1.5

40-40 1.0

a, ~00a 20 0.5

0 ,0.0

0 10 20 30 40 50 60

Time (min)Dive 50. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-25

80 Pressure 2.0P02

60- 1.5

40 1.0

2020 0.5o.

0 L( I 0.0

0 10 20 30 40 50 60

Time (min)Dive 51. Dashed lines indicate PO2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure 2.0P02

60 1.5

40 1.0

0.0 20 0.5

0 _1 0.0

0 10 20 30 40 50 60

Time (min)


A-26

80 -Pressure 2.0P02

60 1.5

4021.

0 10 20 30 40 50 60

Time (mi)


800

80nPressure -• 2.0P02

rCL

.40 1.0

020- 0.5

0 - 1 0.00 10 20 30 40 50 60

Time (min)


A-27

802.80n Pressure +2.0

P02

60 1.5

40 1.0CL

I 20 0.5

0 I !0.0

0 10 20 30 40 50 60

Time (min)

Dive 55. Dashed lines indicate PO2 min (0.16 ATM) and PO 2max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure - 2.0

P02

60 1.5

4040 1.0

20O20- 0.5

0~ 1 0.00 10 20 30 40 50 60

Time (min)


A-28

80 • 'Pressure 2.0P02

60- 1.5;

40 1.0

20 0.5

0 0.0

0 10 20 30 40 50 60

Time (min)


80 Pressure 2.0P02

60 1.5.0 4

40.

O20 0.5

O, 0.0

0 10 20 30 40 50 60

Time (min)


A-29

80- -Pressure 2.0P02

-60 1.5

.c 40 1.00.0

20 0.5

0o1 , ; -0.00 10 20 30 40 50 60

Time (min)Dive 59. Dashed lines indicate PO 2min (0.16 ATM) and PO2max (1.17 ATM)markers. Diver pulled; P0 2 < PO2min before ascent.

80Pressure 2.0P02

40 1.0a)4

S20 0.5

0 I 0.0

0 10 20 30 40 50 60


A-30

80Pressure 2.0P02

60 1.5

40 1.0N

CL 0WO 20 0.5

0 1 1 0.00 10 20 30 40 50 60

Time (min)


80Pressure -1 2.0P02 I

60-

401.

L 200.

S20- 0V.5

0 I 0.0

0 10 20 30 40 50 60

Time (min)


A-31

802.80n Pressure 2.0P02

60 P021.5

40 1.0

020 0.5

0o l, 0.00 10 20 30 40 50 60

Time (min)


80 Pressure 2.0P02

4. 0 "1.5

020 0.5

0 0.0

0 10 20 30 40 50 60


A-32

80-- -Pressure 2.0P02

S60-'I ~1.5-

40 1.0

20-- 0.5

0 10.00 10 20 30 40 50 60

Time (min)


802.80-Pressure 12.0

P02

60--60 1.5

40 1.0

00020- 0.5

0 10 20 30 40 50 60

Time (min)

Dive 66. Dashed lines indicate PO2min (0.16 ATM) and PO2max (1.17 ATM)markers. P0 2 < PO2min during 02 valve actuations. Dive completed withoutviolating P0 2 safety criteria.

A-33

802.80n-Pressure 2.0

P02

60- 1.5

40- 1.00.

O20- 0.5

0 1 0.00 10 20 30 40 50 60

Time (min)


80i " Pressure 2.0P02

60 --- ow' " MimiVIA --' 1.5

40 1.0(N

0. 0

O20-, 0.5

0- 0.00 10 20 30 40 50 60

Time (min)


A-34

80- Pressure - 2.0P02

60--1.U, E

40 -1.nQ. ! 0

I 20 + 0.5

0- 0.00 10 20 30 40 50 60

Time (min)Dive 69. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. P0 2 < PO2min at 02 valve actuation. 02 bottle closed until 10:04 of dive.Diver informed over coms. Dive completed without violating P0 2 safety criteria.Not included in data analyses.

80 Pressure 2.0P02

,60 •-1.5 •= 1 E40 - .0

C - 0.

S20 :- 0.5

0 0.00 10 20 30 40 50 60

Time (min)Dive 70. Dashed lines indicate PO2min (0.16 ATM) and PO 2m.ax (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-35

'Pressure 2.0P02

~60 -''1.5

40 1 .0 wCL 0~4) CL

D20 0.5

0 0.00 10 20 30 40 50 60

Time (min)


80 Pressure 2.0P02

60.. 1.5

40- 1.0 •0

o20 0.5

0 I I 0.0

0 10 20 30 40 50 60

Time (min)

Dive 72. Dashed lines indicate PO2min (0.16 ATM) and PO 2 max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

A-36

80Pressure 2.0P02

60 -.

40 - 1.0

4 00 20 -1 0.5

0 0.00 10 20 30 40 50 60

Time (min)

Dive 73. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. P0 2 < PO2min at 02 valve actuations. Dive completed without violatingP0 2 safety criteria.

80Pressure 2.0P02

60 -"1.5

40

0 _) 0 .5O 20 - .

0 i 10.00 10 20 30 40 50 60

Time (min)


A-37

80 Pressure 2.0

P02

60 1.

40 1.0

C 20 0.5

0 I I 0.0

0 10 20 30 40 50 60


80Pressure 2.0P02

"60 ,1.5

40 1.0C 0O20-- 0.5

0 I I I 0.0

0 10 20 30 40 50 60


A-38

80 2.0-Pressure20

P02

1.5

40 11.0

S20 0.5

0 L i I i i 0.0

0 10 20 30 40 50 60

Time (min)Dive 77. Dashed lines indicate PO 2min (0.16 ATM) and PO 2 max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure 2.0

P02

60 4 .

40-- 1.0

S20 0.5

0- 0.00 10 20 30 40 50 60

Time (min)


A-39

80 'Pressure 2.0P02

60i1

:40 1.0

20 0.5

0 ,0.00 10 20 30 40 50 60


80 Pressure 2.0P02

620 1.5

40- 1.000

Q 20 -0.5

0 J - 0.0

0 10 20 30 40 50 60


A-40

inPressure 2.0P02

•- 60 Ir"" - ,"-'""'"'=" - 1.5 --

40140 -1.

20 - - 0.5

0 I _ 0.0

0 10 20 30 40 50 60

Time (min)


80Pressure 2.0P02

60 1.5 - 1.5

40 1.0

020 -- 0.5

0 0.0

0 10 20 30 40 50 60

Time (min)


A-41

80Pressure 2.0P02

60 1.5

4040 1.0CL 0

S20 0.5

0 I 1-0.0

0 10 20 30 40 50 60

Time (min)


8- Pressure 2.5P02

"60 -" t 2.0

401 6aC4

I 2 0 -- 0 .5

0 1 0.0

0 10 20 30 40 50 60

Time (min)

Dive 84. Dashed lines indicate PO2min (0.16 ATM) and PO2max (1.17 ATM)markers. Diver pulled; P02 > PO2max for at least 10 minutes before ascent (scalemodified to capture elevated data points).

A-42

d-Pressure 2.0P02I

60 "1 .

40 1. .0

a 20 0.5

0 0.00 10 20 30 40 50 60

Time (min)


80Pressure 2.0P02

60 1.5

40 +1.0

O 20 - -0.5

"0 0.0

0 10 20 30 40 50 60

Time (min)

Dive 86. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Data lost before ascent. Dive completed without violating P0 2 safetycriteria. Pre-ascent delay not included in data analysis.

A-43

802.8--Pressure +2.0

P02

60 1.5

40 1. 01

O 20 +0.5

0 0.00 10 20 30 40 50 60

Time (min)

Dive 87. Dashed lines indicate PO 2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Data lost before ascent. Dive completed without violating P0 2 safetycriteria. Pre-ascent delay not included in data analysis.

80Pressure 2.0P02

60 1.5

-40 1.0-110

O20 T 0.S

0 10 20 30 40 50 60

Time (min)

Dive 88. Dashed lines indicate PO2min (0.16 ATM) and PO2max (1.17 ATM)markers. Data lost before ascent. Dive completed without violating P0 2 safetycriteria. Pre-ascent delay not included in data analysis.

A-44

80 Pressure 2.0

P02

U, III-60 ,-.5 T

40 1.0

20-'05

0 lo0.00 10 20 30 40 50 60

Time (min)

Dive 91. Dashed lines indicate PO 2min (0.16 ATM) and PO 2 max (1.17 ATM)markers. Dive completed without violating P0 2 safety criteria.

80Pressure 2.0

P02

60 ~.

-40 -1.0

0- 0.0

0 10 20 30 40 50 60

Time (min)

Dive 92. Dashed lines indicate PO2min (0.16 ATM) and PO 2max (1.17 ATM)markers. Single P0 2 < PO2min at 02 valve actuation. Dive completed withoutviolating P0 2 safety criteria.

A-46

Appendix 8: Dive and iPU 2 Summary Data

RB thru Procedure Preascent Delay AscentDescent Total P0 2 P0 2 P0 2 P0 2 P0 2 P0 2 P0 2 P0 2

Depth Rate BT Dive Time MIN MAX TWA MIN MAX TWA MIN MAXDive (fsw) fsw/min) min) mmin) (atm) (atm) (atm) aatm) atm) atm) (atm) (atm)

1 60.5 33.60 5.83 19.60 0.44 0.56 0.51 0.32 0.79 0.58 0.36 1.902 60.5 33.60 5.83 19.60 0.43 0.55 0.50 0.38 0.43 0.41 0.14 0.383 60.5 33.60 5.83 19.60 0.45 1.43 0.69 0.72 1.81 1.31 0.92 1.32

4 60.5 33.60 5.83 19.60 0.51 0.54 0.53 0.50 0.54 0.52 0.25 0.505 60.4 33.90 5.80 19.60 0.41 0.53 0.49 0.36 0.41 0.39 0.31 1.436 60.4 33.90 5.80 19.60 0.28 0.35 0.31 0.27 0.28 0.28 0.13 0.27

7 60.4 33.90 5.80 19.60 0.42 0.54 0.50 0.36 0.42 0.39 0.10 0.458 60.4 33.90 5.80 19.60 0.46 0.71 0.54 0.52 0.54 0.53 0.42 1.449 60.4 32.00 4.17 17.50 0.52 0.56 0.54 0.43 1.43 0.82 1.22 2.0810 60.4 32.00 4.17 17.50 0.49 0.53 0.51 0.44 0.49 0.47 0.33 1.5911 60.4 32.00 4.17 17.50 0.50 0.55 0.53 0.44 0.50 0.47 0.30 1.9312 60.4 32.00 4.17 17.50 0.47 0.54 0.50 0.43 0.49 0.46 0.31 1.8313 60.5 31.60 4.13 17.50 0.47 0.98 0.67 0.77 0.93 0.85 0.80 1.9714 60.5 31.60 4.13 17.50 0.50 0.57 0.53 0.41 0.49 0.45 0.14 0.4115 60.5 31.60 4.13 17.50 0.38 1.26 0.78 1.32 1.59 1.48 1.16 1.3716 60.1 31.20 4.27 17.37 0.48 0.98 0.59 0.66 0.97 0.78 0.35 1.3417 60.1 31.20 4.27 17.37 0.51 0.55 0.54 0.39 0.50 0.45 0.37 1.4318 60.1 31.20 4.27 17.37 0.52 0.54 0.53 0.46 0.51 0.48 0.18 0.4619 60.1 31.20 4.27 17.37 0.51 0.55 0.53 0.41 0.51 0.48 0.26 1.32

20 60.2 31.50 4.20 17.43 0.42 1.57 0.79 0.91 1.36 1.04 1.03 1.4621 60.2 31.50 4.20 17.43 0.50 1.28 0.79 0.92 1.24 1.11 0.98 1.4522 60.2 31.50 4.20 17.43 0.47 0.90 0.69 0.78 0.89 0.85 0.34 0.8323 60.3 35.60 3.90 17.10 0.49 1.34 0.77 0.82 1.33 1.01 0.82 2.0824 60.3 35.60 3.90 17.10 0.37 1.74 1.15 1.37 1.59 1.48 0.68 1.4125 60.3 35.60 3.90 17.10 0.37 1.61 0.89 0.82 0.88 0.85 0.39 1.1326 60.3 35.60 3.90 17.10 0.51 0.55 0.53 0.43 0.50 0.46 0.15 0.6927 60.3 36.00 3.90 17.03 0.39 0.90 0.63 0.60 0.69 0.65 0.21 0.6028 60.3 36.00 3.90 17.03 0.49 1.39 0.97 0.93 1.00 0.96 0.80 1.1429 60.3 36.00 3.90 17.03 0.50 0.54 0.52 0.37 0.51 0.47 0.36 1.3230 60.2 32.40 12.70 25.70 0.54 0.55 0.55 0.43 1.04 0.77 0.70 1.70

Notes. BT = bottom time; TWA = time-weighted average. Dives (1)-(30) were successful evolutionsexcept for: (2) and (7), P0 2 - 0.16; (4), aborted due to water in rig; (6), aborted due to defective 02fuel cell; and (14) and (18), aborted due to closed 02 bottle. For (26), tabulated minimum P0 2 duringascent reflects a spike that did not persist long enough to warrant dive abort.

B-1

* I .- . ..

ro thru Procedure P reabeei-i L elay i ZMAM

Descent Total P0 2 P0 2 P0 2 P0 2 P0 2 P0 2 P0 2 P0 2Depth Rate BT Dive Time MIN MAX TWA MIN MAX TWA MIN MAX

31 60.2 32.40 12.70 25.70 0.53 0.55 0.54 0.16 0.53 0.36 0.14 1.31

32 60.2 32.40 12.70 25.70 0.49 0.99 0.67 0.79 1.52 1.10 0.57 1.36

33 60.2 32.40 12.70 25.70 0.47 0.78 0.65 0.70 1.40 1.00 1.14 1.4634 60.1 32.40 12.63 25.67 0.43 0.80 0.67 0.57 0.86 0.69 0.54 1.62

35 60.1 32.40 12.63 25.67 0.45 1.02 0.72 0.74 1.72 1.05 1.28 1.82

36 60.1 32.40 12.63 25.67 0.52 0.82 0.64 0.67 1.11 0.79 0.69 1.9037 60.0 32.50 12.70 25.57 0.53 0.55 0.54 0.43 1.07 0.69 0.69 1.75

38 60.0 32.50 12.70 25.57 0.53 0.55 0.54 0.28 0.80 0.49 0.39 1.6539 60.0 32.50 12.70 25.57 0.51 0.65 0.57 0.52 1.51 0.80 0.44 1.4040 60.0 32.50 12.70 25.57 0.50 0.67 0.60 0.54 1.19 0.80 0.77 1.3441 60.0 32.50 12.60 25.57 0.42 1.02 0.76 0.81 1.02 0.91 0.83 1.88

42 60.0 32.50 12.60 25.57 0.47 0.67 0.57 0.45 1.05 0.72 0.43 1.2143 60.0 32.50 12.60 25.57 0.54 0.56 0.55 0.21 0.54 0.39 0.13 1.6844 60.0 33.90 13.37 26.60 0.52 0.57 0.55 0.41 1.03 0.65 0.32 1.1645 60.0 33.90 13.37 26.60 0.49 0.55 0.53 0.10 0.80 0.43 0.28 0.57

46 60.0 33.90 13.37 26.60 0.49 0.55 0.53 0.39 1.21 0.75 0.40 0.9647 60.0 33.90 13.37 26.60 0.48 0.55 0.52 0.10 0.94 0.44 0.16 1.3248 60.0 33.50 13.33 26.63 0.50 0.56 0.52 0.56 1.18 0.81 0.84 1.6949 60.0 33.50 13.33 26.63 0.48 0.53 0.50 0.08 0.92 0.45 0.35 0.7050 60.0 33.50 13.33 26.63 0.52 0.97 0.69 0.66 1.24 0.88 0.48 1.4751 59.9 28.70 13.87 26.73 0.65 1.34 0.96 0.89 1.22 1.01 0.90 1.7552 59.9 28.70 13.87 26.73 0.52 1.13 0.77 0.80 2.00 1.50 0.94 1.8553 59.9 28.70 13.87 26.73 0.47 0.97 0.69 0.54 1.61 1.20 0.89 1.7154 59.9 28.70 13.87 26.73 0.48 1.19 0.84 0.80 1.79 1.43 0.92 1.83

55 59.9 27.60 13.87 26.73 0.48 0.52 0.51 0.31 0.90 0.53 0.70 1.46

56 59.9 27.60 13.87 26.73 0.45 0.73 0.60 0.67 1.70 0.84 0.69 1.2557 59.9 27.60 13.87 26.73 0.48 1.31 0.86 0.94 1.79 1.32 1.02 1.6558 59.9 32.30 13.13 26.20 0.50 0.56 0.54 0.40 1.14 0.66 0.51 1.5959 59.9 32.30 13.13 26.20 0.48 0.56 0.53 0.07 0.89 0.51 0.36 0.7060 59.9 32.30 13.13 26.20 0.47 0.80 0.59 0.49 1.12 0.80 0.54 0.93

Notes. BT = bottom time; TWA = time-weighted average. Dives (31)-(60) were successful evolutionsexcept for: (45), (49), and (59), in which P0 2 < 0.16. For dives (31), (43), and (47), tabulated values ofminimum P0 2 < 0.16 reflect spikes that did not persist long enough to warrant dive abort.

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RB thru Procedure Preascent Delay AscentDescent Total P0 2 P0 2 P0 2 P0 2 P0 2 P0 2 P0 2 P0 2

Depth Rate BT Dive Time MIN MAX TWA MIN MAX TWA MIN MAXDive fsw)/ fsw/min)(min) (min) (atm) am tmt (atm)

61 59.9 32.30 13.13 26.20 0.54 1.02 0.80 0.68 0.98 0.79 0.88 1.3762 60.0 33.20 13.13 26.23 0.38 1.05 0.69 0.48 1.28 0.84 0.83 1.7263 60.0 33.20 13.13 26.23 0.43 1.06 0.80 0.72 1.16 0.97 0.47 0.9964 60.0 33.20 13.13 26.23 0.44 1.00 0.66 0.59 0.86 0.69 0.80 1.3065 60.3 31.70 32.70 45.83 0.44 0.56 0.48 0.46 1.58 1.07 1.04 1.4466 60.3 31.70 32.70 45.83 0.46 0.49 0.47 0.12 0.85 0.38 0.38 1.5467 60.3 31.70 32.70 45.83 0.41 1.46 1.03 1.15 1.36 1.24 1.23 1.8868 60.3 31.70 32.70 45.83 0.40 1.24 0.79 0.86 1.83 1.30 0.96 1.5769 60.2 31.50 32.77 45.83 0.47 0.50 0.49 0.08 1.45 0.86 0.63 1.2870 60.2 31.50 32.77 45.83 0.61 1.70 1.27 0.90 1.61 1.08 0.84 1.4571 60.2 31.50 32.77 45,83 0.48 0.72 0.61 0.55 0.93 0.71 0.66 1.6272 60.3 34.50 32.63 45.70 0.46 0.49 0.48 0.20 1.16 0.54 0.73 1.6573 60.3 34.50 32.63 45.70 0.46 0.50 0.49 0.10 0.90 0.39 0.11 1.0774 60.3 34.50 32.63 45.70 0.40 1.99 1.15 0.86 1.54 1.12 1.05 1.4775 60.3 34.50 32.63 45.70 0.39 1.15 0.77 0.65 1.22 0.97 0.87 1.4176 60.3 34.60 32.50 45.70 0.47 0.60 0.54 0.50 0.93 0.79 0.83 1.8177 60.3 34.60 32.50 45.70 0.51 0.54 0.53 0.34 0.73 0.55 0.25 0.6878 60.3 34.60 32.50 45.70 0.47 0.51 0.50 0.14 0.75 0.42 0.40 1.2079 60.2 31.00 32.87 45.83 0.47 0.62 0.55 0.38 1.40 0.69 0.31 0.8680 60.2 31.00 32.87 45.83 0.44 0.72 0.61 0.42 0.93 0.63 0.90 1.3281 60.2 31.00 32.87 45.83 0.46 0.93 0.75 0.73 1.85 1.35 0.86 1.7282 60.2 31.00 32.87 45.83 0.40 0.98 0.73 0.89 1.99 1.34 0.81 1.4883 60.1 31.20 32.77 45.80 0.47 1.07 0.67 1.01 1.50 1.7 1.05 1.7084 60.1 31.20 32.77 45.80 0.50 1.06 0.76 0.81 2.13 1.84 0.96 2.0585 60.1 31.20 32.77 45.80 0.51 0.54 0.53 0.41 1.46 0.94 0.50 1.1386 59.9 -0.60 14.63 27.70 * 0.00 0.00 0.11 1.20 0.85 0.48 1.1687 59.9 -0.60 14.63 27.70 * 0.00 0.00 0.09 1.54 1.09 0.96 1.5488 59.9 -0.60 14.63 27.70 * 0.00 0.00 0.15 1.37 0.74 0.92 1.5489 59.9 -0.60 14.63 27.70 * 0.00 0.00 0.15 1.05 0.56 0.95 1.2590 60.2 31.80 33.57 46.63 0.48 0.96 0.78 0.80 1.88 1.54 0.82 1.7191 60.2 31.80 33.57 46.63 0.49 0.99 0.65 0.44 1.60 0.84 0.83 1.38

92 60.2 31.80 133.57 46.63 0.49 0.63 0.57 0.13 1.21 0.64 0.51 1.20

Notes. BT = bottom time; TWA = time-weighted average. Dives (61)-(92) were successful evolutionsexcept for: (90), in which P02 > 1.7 for 10 minutes; (66), (73), and (78), in which tabulated values ofminimum P0 2 < 0.16 reflect spikes that did not persist long enough to warrant dive abort; and (86),(87), (88), and (89), in each of which real-time data logging failed during RB thru Procedure forapproximately 10 minutes.

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